<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>变量的特点</title>
  <script>
    function f1(){
      let i=1;
      //适用于所有类型,typeof打印的是变量类型
      console.log(i)
      //   number类型,只要是数字都是number类型
      console.log(typeof 1)

      i="admin"
      console.log(i)
      console.log(typeof (i))
      i='c'
      console.log(i)
      console.log(typeof i)

    }
  </script>
</head>
<body>
<button onclick="f1()">变量的特点</button>
</body>
</html>